This description relates to authenticating access terminal sessions.
Audio, video and multimedia content may be passed and shared among wireless devices such as cellular phones, personal digital assistants (PDAs) and computer systems (also referred to as Access Terminals or ATs). To share this content, the ATs may incorporate wireless technology such as High Data Rate (HDR) technology that enables personal broadband Internet services. Such technology may comply with standards such as an EV-DO Rev A standard (also written as 1×EV-DO Rev A or 1× Evolution-Data Optimized Revision A) or another similarly capable standard. EV-DO Rev A is included in a family of standards that are promoted by the Third Generation Partnership Project 2 (3GPP2), a collaborative Third Generation (3G) telecommunications specification-setting project associated with the development of the next generation Code Division Multiple Access (CDMA) wireless communications.
The 1×EV-DO protocol is an EVolution of the 1×RTT standard for high-speed data-only (DO) services and has been standardized by the Telecommunication Industry Association (TIA) as TIA/EIA/IS-856, “CDMA2000 High Rate Packet Data Air Interface Specification”, 3GPP2 C.S0024-0, Version 4.0, Oct. 25, 2002, which is incorporated herein by reference. Revision A to this specification has been published as TIA/EIA/IS-856, “CDMA2000 High Rate Packet Data Air Interface Specification”, 3GPP2 C.S0024-A, Version 2.0, June 2005, which is also incorporated herein by reference. Revision B to this specification has been initiated as TIA/EIA/IS-856, “CDMA2000 High Rate Packet Data Air Interface Specification,” 3GPP2 C.S0024-B, Version 1.0, March 2006 and is incorporated herein by reference.
A 1×EV-DO radio access network (RAN) includes ATs in wireless communication (e.g., over airlinks) with radio nodes (RNs) and that support 1×EV-DO. The radio nodes are connected to radio node controllers (RNCs) over a backhaul network that can be implemented using a shared IP or an Ethernet network (e.g., metropolitan Ethernet network) that supports many-to-many connectivity between the radio nodes and the radio node controllers. The radio access network also includes a packet data serving node, which is a wireless edge router that connects the RAN to the Internet.
To provide wireless coverage, the radio node controllers and the radio nodes of the radio access network can be grouped into clusters (referred to as radio node controller clusters). The geographical coverage area provided by each radio node controller is defined as a single 1×EV-DO subnet.
Each radio node is primarily associated with the radio node controller in its subnet, however, the radio node may also be associated (referred to as a secondary association) with a radio node controller in another subnet (e.g., an adjacent subnet). Generally, when primarily associated with a radio node controller, messages may be exchanged over one or more channels (e.g., a forward traffic channel, a reverse traffic channel, a control channel, an access channel, etc.). For a secondary association, messages may be exchanged over one or more channels, however messages are not exchanged over an access channel. Additional information concerning the primary associations of radio nodes and radio node controllers are described in U.S. application Ser. Nos. 11/037,896 filed on Jan. 18, 2005, 09/891,103, filed on Jun. 25, 2001, and 10/848,597, filed on May 18, 2004, and incorporated herein by reference. Correspondingly, information concerning the secondary associations between radio nodes and radio node controllers are described in U.S. application Ser. Nos. 11/305,286, filed on Dec. 16, 2005, and incorporated herein by reference.
Typically, in a scenario in which an AT crosses over the border from one subnet (“a source subnet”) to another subnet (“a target subnet”), an A13 dormant handoff is performed between the radio node controllers of the source and target subnets. A dormant handoff is triggered by a receipt of a request message (i.e., a UATI_Request message) sent by the transitioning AT. The AT sends the request message upon realizing it has crossed over a border from one subnet to another. In some examples, the AT monitors a unique 128-bit identifier (i.e., a SectorID) of a sector parameter message that is broadcasted by each sector. All sectors that belong to the same subnet have SectorIDs that fall within a certain range. For each AT that falls within this range, a unicast access terminal identifier (UATI) (e.g., a 32-bit binary number) is assigned by a radio node controller of the particular subnet. When the access terminal moves into the coverage area of another subnet, the AT compares its UATI with the SectorID of the sector parameter message being broadcasted by the new sector. When the UATI and the SectorID do not belong to the same range, the AT sends a UATI_Request message over the access channel of the new radio node, which routes the message to the radio node controller with which it has a primary association (in this case, the radio node controller of the target subnet). The radio node controller responds to the receipt of the UATI_Request message by initiating a dormant handoff with the radio node controller of the source subnet.
To grant a handoff from the source subnet to the target subnet, the 3GPP2 standard promotes using security layer protocols to authenticate the AT. However, some ATs, AT manufacturers and Access Network (AN) manufacturers do not support the 3GPP2 security layer protocols. Thereby, a number of ATs denied access may increase absent compliance with the security protocols.